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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 5 |
| 3 | 29 |
| 4 | 181 |
| 5 | 1181 |
| 6 | 7941 |
| 7 | 54573 |
| 8 | 381333 |
| 9 | 2699837 |
| 10 | 19319845 |
| 11 | 139480397 |
| 12 | 1014536117 |
| 13 | 7426790749 |
| 14 | 54669443141 |
| 15 | 404388938349 |
| 16 | 3004139083221 |
| 17 | 22402851226749 |
| 18 | 167640057210981 |
| 19 | 1258340276153229 |
| 20 | 9471952718661621 |
| 21 | 71481616200910749 |
| 22 | 540715584181142661 |
[1,1,5,29,181,1181,7941,54573,381333,2699837, 19319845,139480397,1014536117,7426790749, 54669443141,404388938349,3004139083221, 22402851226749,167640057210981,1258340276153229, 9471952718661621,71481616200910749, 540715584181142661] |